class THaS2CoincTime: public THaCoincTime

 To construct, specify the name of the module (usually "CT"),
 a description ("Coincidence time calculation between L and R HRS"),
 the FIRST and SECOND source of tracks ("L" and "R"),
 the MASSES in GeV/c^2  of the particles in FIRST and SECOND spectrometers.

 The rest of the parameters are usually not used.

 The next two are thes name of the TDC channels in the database for this
 object measuring the difference between the COMMON STARTS of the FIRST
 and SECOND spectrometers, such that:

  * ch_name1 measures  COMMON_START<sub>2</sub> - COMMON_START<sub>1</sub>,
  * ch_name2 measures  COMMON_START<sub>1</sub> - COMMON_START<sub>2</sub>.

  These default to "ct_(spec2 name)by(spec1 name)" and
  "ct_(spec1 name)by(spec2 name)", respectively.

  * detname1 is the name of the timing plane in the FIRST spectrometer to
        use to measure the time of the track in this spectrometer.
  * detname2 is likewise the name of the timing plane in the SECOND
        spectrometer. If not specified, detname1 is used.

  The default arguments are detname1="s2", and detname2 be assigned to
  match detname1.

 just be certain to call THaCoincTime's destructor

 Initialize the module. Grab the global variables containing the tracking
 results (including calculated pathlengths) and the times and pads from the
 THaScintillator planes.

 Read in coincidence TDC's, calculate the time of the tracks at the
 target vertex, and then assemble the time-difference between when the
 tracks left the target for every possible combination.